Electromagnetic vibrator

ABSTRACT

An electromagnetic vibrator wherein the armature is coupled to and supported on its associated mass by means of an adjustable coupling arrangement so that the armature and its mass are spaced from one another. A central disc spring element is arranged between the armature and the associated mass to bias these elements away from each other with a force sufficient to prevent relative movement between the armature and its associated mass. One or a plurality of disc springs may be used, and a guide means is generally provided on the mass for positioning the spring or springs. By adjusting the coupling means, and consequently the bias face exerted by the disc spring, the space between the armature and its associated mass is varied which simultaneously varies the operational air gap of the vibrator between the armature and its associated core.

United States Patent 1 111 3,775, 25 1145 Nov."27,1973

ELECTROMAGNE IC 'VIBRATOR [75] inventors: Leo Brosch, Stetten; Gerd Fechner,

, Goppingen; Eduard Reichert, Stuttgart-Rot, all of Germany [73] Assignee: Transformatoren Union Aktiengesellschaft, Stuttgart,

Germany 2211mm Nov. 6, 1972 211 Appl. No.2 303,823

Related US. Application Data [63] Continuation-impart of Ser. No. 88,665 Nov. 12,

l970, abandoned.

[30] Foreign Application Priority Data v I Nov. l5, 1969 Germany P 19 57 585.0

[52] US. Cl. 310/19, 310/29 [51] int. Cl. H02k 33/02 [58] Field of Search 310/17, 18, 28, 29,

[56] References Cited UNiTED STATES PATENTS 3,170,078 2/l965 Kuschel ..3l0/29 3,167,670 1/1965 s purlin ..310/29 3,107,905 10/1963 Lucas 267/161x Primary Examiner-D. F. Duggan Attorney-George l-l. Spencer et al.

[57] ABSTRACT An electromagnetic vibrator wherein the armature is coupled to and supported on its associated mass by means of an adjustable coupling arrangement so that the armature and its mass are spaced from one another. A central disc spring element is arranged beally provided on the mass for positioning the spring or springs. By adjusting the coupling means, and consequently the bias face exerted by the disc spring, the space between the armature and its associated mass is varied which simultaneously varies the operational air gap of the vibrator between the armature and its associated core.

10 Claims, 13 Drawing Figures C'OEE be sufficiently dependable in the long run, because of the vibrations and shaking forces, whereas the use of bolts with nuts and lock-nuts (FIG. 4) requires a relatively large. area for. their installation. This is uneconomical in small vibrators due to the high weight to horsepower ratio.

In each one of the known constructions described above the vibrator drive must always be de-energized when'the air gap is to be adjusted, because only in the rest state can the clampingelements be handled. The air gap adjustment thus constitutes a time-consuming testing, or trial-and-error procedure, until the optimum setting has been found.

FIGS. 5a and 5b show an embodiment of the present invention in which a large, centrally located disc spring 3, constructed from a suitable, known material, is inserted between the four setting bolts 4 arranged in the four corners of the armature coupling piece 1 of the free mass of the-vibrator and an armature 2 to hold together the coupling piece 1 and the armature 2.

If the spring force of one disc. spring by itself is not sufficient, two disc springs 3 can be disposed, as shown in FIG. 6, in an opposed relationship; for example, in series. If the spring force is insufficient for example, if natural vibrations develop between the free mass 1 and the armature 2 two or moredisc springs may be connected in the same direction; that is, in parallel. FIG. 7 shows a pair of two parallel connected disc springs arranged in series.

As a guide for one or a plurality of springs, a central cylindrical guide 6,6',6" protrudes from the coupling piece 1 (FIGS. 5,6 and 7). The embodiments of FIGS. 6 and 7 have a corresponding recess 7 disposed in the armature 2 opposite this guide so that the guide can move into this recess when the springs are pressed together.

It is, however, also possible to guide one or a plurality of springs 3' along the external diameter by means of a centrally located, cylindrical recess 8 in the coupling piece 1 (FIGS. 8:; and 8b).

I Referring now to FIG. 9 there is shown an emboditending arms 16. Fastened to the top of these arms 16 by means of bolts 17 are the respective ends of the leaf springs 18 which provide the vibratory motion of the vibrator.

The freemass of the vibrator, which includes a 5 weight portion 20 and the armature coupling piece 1,

and the core armature 2, which is fastened to the coupling piece 1 by means of bolts 4, are. attached tothe I center of the leaf springs 18 bymeans of one or more bolts 19. According to the illustrated embodiment of the invention, a single cup spring 3 is clamped between I the armature coupling piece 1 and the core armature 2. The degree of pretensioning or'biasing force exerted by the spring 3 is determined 'by the setting of the screws 4 by means. ofwhich the air space 21 between the armature coupling piece 1 and the armature 2 can be adjusted. Adjusting the air space 22 simultaneously adjusts and sets the operating air gap 22 between the I armature 2 and the pole surfaces of the open core. 12.

FIG. 10 illustrates the armature mounting arrangement according to the present invention whereby the operational air gap may be set by means of a cup spring 3 for a vibrator employing helical springs 23 for providing the vibrator motion. In this type of vibrator the edge of the weight portion 20 of the free mass serves'as an abutment for the helical springs 23 and the free mass is guided at each end by a long continuous bolt 24 which is fastened to the supporting frame or base 11.

The operation of the present invention can be clearly seen in the two drawings.

- Tightening of bolts 4 against the pressure of cup spring 3 causes the distance 21 between the armature support or coupling piece 1 and the armature 2 to be reduced, so that the'operating air gap 22 between the armature 2 and core l2 is increased and viceversa.

The present invention permits the continuous setting of the desired operating air gap without any complicated installation work.- That is with the arrangement of the present invention, the operating air gap 22 can be adjusted merely by tightening bolt 4 evenduring operation, so that the field test operations require only a fraction of the time required for the known methods. Moreover, since the adjustment of the air gap is accomplished solely by adjusting the position of the armature 2 relative tothe coupling piece 1 of the free mass, the pretensioning of the operating springs required for the vibration, i.e.,' the springs 18 or 23, is in no way effected by the setting of the air gap.

Of course, a prerequisite for proper functioning of the invention is that bolts 4 remain in the set position and can not yield during operation. If the thread bores for holding the bolts-4 are directly placed in a known laminated armature, the seat for the bolts is naturally extremely tight. A further improvement is realized when oversize bolts are used, for example with a particularly heavy, known, electrolytic protective coating.

Other possibilities are to insert a known synthetic resin adhesive into the threads, which hardens some time after the completed adjustment and which produces a practically unseparable connection between the bolts and the thread bore.

Or, further thread bores which are arranged transverse to the first thread bores, such as shown in FIGS. 6 and 7 and designated by the reference numeral 5, can be provided with which the sheets of a laminated armature 2 (laminations not shown) are clamped together, thus clamping in setting bolts 4. The laminations are, of course, parallel to the plane of the paper in FIGS. 6 and '7.

It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and the same are in-.

c. a centrallylocated disc spring means arranged between said armature and said associated mass and exerting a sufficient force for biasing said armature and associated mass so that, in cooperation with '5 said'adjustable coupling means, a desired airi space setting is maintained between saidarmature and said associated mass and said armature and said associated mass-move as a unit during vibration of the vibrator, whereby by adjustingsaid coupling means, said airspace and consequently the operational air gap of said vibrator adjacent said armature is adjusted without affecting the vibrating i wherein one of said armature and said associated mass defines a guide means for said spring means.

6. An electromagnetic vibrator as defined in claim 5, wherein said guide means is a centrally located, cylindrical member protruding from said associated mass.

7. An electromagnetic vibrator as defined inclaim 6, further including a recess defined in said armature for receiving said member.

8. An electromagnetic vibrator as defined in claim 5,

6 wherein said guide means, is a centrally located, cylindrical recess defined in said associated mass andconfiguredto receive at least one of said discsprings. "9; Man electromagnetic vibrator including a magnetic armature mounted for vibratory movement relative to a magnetic core, and a free mass associated with said armature, the improvement comprising:

an adjustable means for coupling said armature to said mass so that said armature is adjustably displaceable relative to said free mass in the direction of the vibratory movement of the vibrator; and centrally located disc spring means arranged between said armature and said free mass for biasing said armature and said free mass apartto provide an air space therebetween, said spring means exerting a sufficient force so that said armature and said associated mass move as a unit during vibration of the vibrator, whereby adjustment of said coupling means varies the position of said armature relative to said mass and thereby the operational air gap of said vibrator between said armature and said core.

10. The electromagnetic vibrator as defined in claim 9 wherein said adjustable coupling means comprises an armature coupling piece which forms part of said mass and which extends parallel to the plane of said armature, and a plurality of bolts extending through openings in said coupling piece and threadingly engaging said armature. 

1. In an electromagnetic vibrator including an armature, the improvement comprising: a. a mass associated with said armature and spaced therefrom to define an air space therebetween; b. adjustable means coupling said mass to said armature; and c. a centrally located disc spring means arranged between said armature and said associated mass and exerting a sufficient force for biasing said armature and associated mass so that, in cooperation with said adjustable coupling means, a desired air space setting is maintained between said armature and said associated mass and said armature and said associated mass move as a unit during vibration of the vibrator, whereby by adjusting said coupling means, said air space and consequently the operational air gap of said vibrator adjacent said armature is adjusted without affecting the vibrating characteristics of the vibrator.
 2. An electromagnetic vibrator as defined in claim 1, wherein said disc spring means has at least two oppositely directed and contacting disc springs.
 3. An electromagnetic vibrator as defined in claim 2, wherein said disc spring means is a plurality of disc springs arranged in a combination of oppositely directed springs and same directed springs.
 4. An electromagnetic vibrator as defined in claim 3, wherein at least two contacting disc springs are arranged in the same direction.
 5. An electromagnetic vibrator as defined in claim 4, wherein one of said armature and said associated mass defines a guide means for said spring means.
 6. An electromagnetic vibrator as defined in claim 5, wherein said guide means iS a centrally located, cylindrical member protruding from said associated mass.
 7. An electromagnetic vibrator as defined in claim 6, further including a recess defined in said armature for receiving said member.
 8. An electromagnetic vibrator as defined in claim 5, wherein said guide means is a centrally located, cylindrical recess defined in said associated mass and configured to receive at least one of said disc springs.
 9. In an electromagnetic vibrator including a magnetic armature mounted for vibratory movement relative to a magnetic core, and a free mass associated with said armature, the improvement comprising: an adjustable means for coupling said armature to said mass so that said armature is adjustably displaceable relative to said free mass in the direction of the vibratory movement of the vibrator; and a centrally located disc spring means arranged between said armature and said free mass for biasing said armature and said free mass apart to provide an air space therebetween, said spring means exerting a sufficient force so that said armature and said associated mass move as a unit during vibration of the vibrator, whereby adjustment of said coupling means varies the position of said armature relative to said mass and thereby the operational air gap of said vibrator between said armature and said core.
 10. The electromagnetic vibrator as defined in claim 9 wherein said adjustable coupling means comprises an armature coupling piece which forms part of said mass and which extends parallel to the plane of said armature, and a plurality of bolts extending through openings in said coupling piece and threadingly engaging said armature. 